The object had ten kilometers in diameter and
scientists have not yet determined exactly whether it was a meteorite or comet,
but agree that their average speed was 25 to 30 kilometers per second and left
a footprint impact (crater) of approximately 200 kilometers in diameter.
After impact the earth was plunged into total chaos. Caused large fires
occurred due to a temperature of up to 20 thousand degrees Celsius were
recorded throughout the Americas, there were earthquakes whose intensities
ranged from 14 to 16 degrees Richter and other disturbances that resulted in
numerous seismic and volcanic eruptions. In addition, heavy rains were
present acidic and formed huge waves, which now are known as tsunami (Japanese
word derived from), traveling horizontally at speeds of up to 750 mph and reach
between 15 30 meters in height. In the case of the Chicxulub impact has
been estimated that the tsunami could have reached heights of 100 to 200
meters, says the geologist José Manuel Gradates Nishimura, investigator
assigned to the Program of naturally fractured reservoirs, the Mexican
Petroleum Institute (IMP).
Because of the immensity of the impact, the earth underwent significant
changes, which ended in a massive way with about 70 percent of the life forms
that existed at that time (Cretaceous Tertiary boundary, better known as KT),
including the dinosaurs. "For several months or even years the land
was plunged in total darkness due to dust (ash) and smoke thrown and distributed
globally that gradually blocked the sunlight, as a result there was an intense
winter cold that, similarly, lasted several years and destroyed the flora (in
the absence of photosynthesis) and thus the food chain. "
Scientific
research
In those years it was thought possible to find oil, but so far no hydrocarbons
have been located. By 1980, the Premix geophysicist Antonio Cameron
conducted research to study structures that might contain oil, but found a
depression that he thought might be due to a meteorite impact or have a direct
relationship with a volcano, refers Nishimura Gradates geologist.
However, after several scientific investigations include studies of geology,
mineralogy, and tectonics of the Yucatan Peninsula, the engineer Cameron with
other specialists from several countries indicated that the planar deformation
features present in the rocks of the Chicxulub crater, could only be operated
from the impact of nuclear explosions or extraterrestrial objects. Also,
located at the site mineral planar deformation associated with the glass (molten rock). Another important
checkpoint was originally the locationof a chemical element called
iridium. Iridium belongs to the platinum group and is very scarce in the
land, but in meteorites. And various extraterrestrial objects is found
abundantly. This element was deposited with other sediments in the layer
of the earth during the Cretaceous age limit Tertiary (KT).
.
The first
investigations of the IMP
In 1991, IMP researchers collaborated in further studies with the working group
of Dr. Walter Alvarez of the University of California and much of the crater
researcher, tells the geologist Gradates Nishimura. The investigations
included in the analysis of various rocks and elements linked to the Chicxulub
impact. The next year, scientists at the IMP in the journal Science
published an article about the study and analysis of certain rocks melt
extracted from the area through a perforation of Premix. "These rocks
were 65 million years, which strengthens the relationship between impact and
the time that the mass extinction occurred (not all), including the
dinosaurs."
Since the beginning of the last decade, researchers at the IMP have
collaborated on a permanent basis in the various studies of Chicxulub crater.
There is no oil or
A geologist said Gradates Nishimura, in the impact zone no organic rock that
could generate hydrocarbons. In contrast, the marine deposits found in the
Gulf of Mexico have a direct relation to the impact. "The age gap
carbonated KT and storing hydrocarbons, originated as a result of seismicity,
sedimentation of different materials and marine tsunami
disturbance." In addition, a large percentage of the upper seal layer
of the reservoir (marine area) is composed of clay minerals formed by alteration
of glassy material from the Chicxulub impact.
The Alvarez Theory
Alvarez theory is known as the proposal of Dr. Wilson Alvarez, professor of
geology and geophysics at the University of California, Berkeley, member of the
U.S. National Academy of Sciences and researcher of the crater. This
hypothesis (published in 1980 in the journal Science) suggested that mass
extinctions that marked the end of the Mesozoic Era and the beginning of the
Cenozoic were due to the impact of a huge meteorite. Alvarez theory was
based on scientific studies reporting Alvarez and collaborators, in which
reference was made to anomalous high content of iridium in the clay layer that
marks the boundary between these two eras.
The article documented interpretations of the consequences of an impact of that
magnitude. If there was an impact, where's the crater? From these
statements several groups of researchers in the world were given the task of
locating the crater that may have left the impact of extraterrestrial object,
explains geologist IMP.
.
The most recent
There is now an international research group, led by the Institute of Geology
and Geophysics, National Autonomous University of Mexico (UNAM), which
conducted a detailed study of rocks disturbed by the impact, and those that
were generated thereafter. To this end, the structure of the crater drill
depths of 2.5 km.
In turn, researchers at the Mexican Petroleum Institute will carry out studies
of sediment logy, geochemistry and probably of paleontology in the samples obtained. The
project also involved specialist Federal Electricity Commission (CFE), the
University of Yucatan and of the International Continental Scientific Drilling
(ICDP for its acronym in English). In doing so, researchers at the IMP are
relying on different techniques such as sediment logy, micropaleontology,
geochemistry and geochronology, among others.
The primary objective of the multidisciplinary study is to establish, with
greater particularity, what happened in the moments subsequent to impact, how
it affected the support systems of life and what happened to the weather, among
other scientific mysteries.
Finally, although Chicxulub impact crater has a really preserved, Gradates
Nishimura said that the drilling of the crust of the crater is difficult and
expensive, especially if they are to recover, by way of columns, continuous
samples of rock. It is noteworthy that most of these processes are carried
out drilling in order to find oil source rock and not purely academic purposes,
as in this case.
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